Impact rudder

Abstract

A rudder for a water craft is constructed to automatically compensate for impact on the rudder while the craft is maneuvering. The lower portion of the rudder is mounted to an upper portion by a pin. The lower portion can pivot about the pin to reduce drag and draft. The lower portion is spring loaded to return to the original position after impact.

What is claimed is:  
     
       1. In a boat having a hull, said hull formed with at least one tunnel, a propulsion system having a propeller shaft connected to a propeller disposed in said tunnel, with said propeller providing the sole source of forward movement, and a rudder providing the sole source of directional control, said rudder depending from said hull in said tunnel, said rudder comprising an upper body and a lower body, said upper body connected to said directional control system, said lower body is rotatably connected to said upper body at a pivot point, said pivot point being spring loaded whereby in response to an impact upon said lower body said lower body rotates about said pivot point. 
     
     
       2. In a boat of  claim 1  wherein said pivot point includes a spring, said spring providing resilient force to maintain said upper body and said lower body in an at-rest position. 
     
     
       3. In a boat of  claim 2  wherein said spring is loaded as said lower body rotates about said pivot point in response to said impact, said spring automatically unloading to return said lower body to said at-rest position after impact. 
     
     
       4. In a boat of  claim 3  wherein said upper body has a periphery comprising a leading edge, a bottom edge and a trailing edge, said trailing edge containing a slot, said lower body mounted in said slot and extending below said bottom edge of said upper body, and said spring located in said slot between said upper body and said lower body whereby said lower body rotates into said slot upon impact. 
     
     
       5. In a boat of  claim 3  wherein said boat has a keel and said upper body terminates approximately coplanar with said keel. 
     
     
       6. A boat of  claim 1  wherein said propeller is a super cavitating propeller. 
     
     
       7. In a boat having a hull with a keel, a propulsion system, said propulsion system having a propeller shaft and a propeller secured to said shaft, said propeller depending below said keel, and a directional control system including a depending rudder, said rudder comprising an upper body and a lower body, said upper body connected to said directional control system, said lower body rotatably connected to said upper body at a pivot point, said pivot point includes a spring, said spring providing resilient force to maintain said upper body and said lower body in an at-rest position, said spring loaded as said lower body rotates about said pivot point in response to said impact, said spring automatically unloading to return said lower body to said at-rest position after impact whereby in response to an impact upon said lower body said lower body rotates about said pivot point, said upper body terminating approximately coplanar with said propeller. 
     
     
       8. In a boat having a hull, a propulsion system and a directional control system including a depending rudder, said rudder comprising an upper body and a lower body, said upper body connected to said directional control system, said lower body is rotatably connected to said upper body at a pivot point whereby in response to an impact upon said lower body said lower body rotates about said pivot point, said pivot point includes a spring, said spring providing resilient force to maintain said upper body and said lower body in an at-rest position, said spring loading as said lower body rotates about said pivot point in response to said impact, said spring automatically unloading to return said lower body to said at-rest position after impact wherein said propulsion system has a propeller shaft with a super cavitating propeller secured to said shaft, said pivot point approximately coplanar with said propeller shaft.